"Sun, 04 Jan 1970 20:39:36"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700104
Only TIME
20:39:36
General datetime
1970-01-04 20:39:36Z
For Database
1970-01-04 20:39:36
For HTTP1.1
Sun, 04 Jan 1970 20:39:36 GMT